The autopsy on James Hellwig was conducted by the Maricopa County Medical Examiner's Office on Thursday.
Hellwig, 54, collapsed while he was walking his wife to their car at a Scottsdale hotel on April 8. The former pro wrestler was rushed to an area hospital, where he was pronounced dead.
The Ultimate Warrior was one of pro wrestling's biggest stars in the late 1980s. He began his WWE career in 1987. He defeated Hulk Hogan at WrestleMania VI to become WWE Champion.
Hellwig is survived by his wife, Dana, and his two daughters, according to WWE.
The Associated Press contributed to this report.